System and method for the deployment of a hydroelectric turbine

ABSTRACT

The present invention is concerned with a system and method for the deployment of a hydroelectric turbine, and comprises a base and vessel beneath which the base can be secured, and to which base, from above deck, a hydroelectric turbine can be secured to the base and subsequently released with the base from the vessel.

FIELD OF THE INVENTION

The present invention is concerned with a system and method for thedeployment of a hydroelectric turbine, and in particular a system andmethod which significantly simplifies the transportation of ahydroelectric turbine and associated base to a deployment site, inaddition to simplifying the subsequent deployment of the turbine andbase to the seabed.

BACKGROUND OF THE INVENTION

Due to the environmental damage which has been inflicted on the planetas a result of the burning of fossil fuels, renewable energy has finallybegun to be given significant attention, with many projects beingdeveloped around solar energy, wind energy, and tidal power. Of thesealternative forms of energy, tidal power is arguably the mostattractive, given that tidal flows are entirely predictable andconstant, unlike wind or solar energy which are relatively intermittentand therefore less dependable.

However, harnessing tidal energy does provide its own challenges, inparticular with respect to the installation and maintenance of tidalpower generators, for example hydro-electric turbines, which by the verynature of the operation of same must be located in relatively fastflowing tidal currents, and more than likely located on the seabed. Inaddition, in order to be economically viable these turbines must bebuilt on a large scale.

As a result the turbines and associated bases/supports are large andcumbersome components, and require significant heavy lifting andtransport equipment in order to achieve deployment. The use of suchheavy lifting equipment is normally a hazardous undertaking, and isrendered even more dangerous when this equipment is operated at seaunder difficult and unsteady conditions.

The installation process is further complicated by an increasingshortage in the market of suitable vessels and equipment to perform suchdrilling work and the extreme danger of engaging divers in high tidalflow sites.

The present invention has therefore been developed with a view tosimplifying the deployment of hydroelectric turbines, and which systemand method allow the deployment of a hydroelectric turbine which hasbeen pre-installed on a base.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provideda hydroelectric turbine deployment system comprising a base and ahydroelectric turbine supportable on the base; a marine vessel adaptedto releasably retain, when afloat, the base therebeneath; wherein thevessel is adapted to allow the base to be released and lowered awayfrom, and/or raised under and connected to, the vessel; and in which thebase comprises a support which projects, when the base is connectedbeneath the vessel, upwardly through the vessel; characterised in thatthe vessel comprises a portal through which the support projects whenthe base is mounted beneath the vessel and through which the supportmounted turbine can pass.

Preferably, the vessel comprises load bearing means adapted to raiseand/or lower the base relative to the vessel.

Preferably, the load bearing means comprises one or more winches.

Preferably, the vessel comprises at least a pair of hulls connectedtogether.

Preferably, the system is adapted to enable ballast to be secured to thebase when the base is secured beneath the vessel.

Preferably, the vessel is modular.

According to a second aspect of the present invention there is provideda method of

deploying a hydroelectric turbine comprising the steps of;

securing a base for the turbine beneath a vessel;

securing the turbine to a support of the base which projects upwardlythrough the vessel;

transporting the vessel to a deployment site;

releasing the base from beneath the vessel;

characterised in that in the step of releasing the base from beneath thevessel, allowing the turbine to pass through the vessel.

Preferably, the method comprises, in the step of securing the base,locating the base on the

bottom of a body of water;

positioning the vessel above the base;

and raising the base into position beneath the vessel.

Preferably, the method comprises the step of securing one or morelifting lines to the base prior to locating the base on the bottom ofthe body of water.

Preferably, the method comprises, in the step of raising the base intoposition beneath the vessel, utilizing load bearing means on the vessel.

Preferably, the method comprises the further step of adding ballast tothe base subsequent to securing the base beneath the vessel.

Preferably, the method comprises securing the support to the basesubsequent to securing the base beneath the vessel.

Preferably, the method comprises the further step of testing variousoperating parameters of the base and/or turbine at a test location priorto deploying the base at the deployment site.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a base for a turbine standing on a quay;

FIG. 2 illustrates the base of FIG. 1 having being lowered to the seabedadjacent the quay;

FIG. 3 illustrates a deployment vessel floating above the base andadjacent the quay;

FIG. 4 illustrates the vessel of FIG. 3, following the raising of thebase into position directly beneath the vessel;

FIG. 5 illustrates the vessel and base of FIG. 4, in which a pair ofsupports have been secured through the vessel to the base;

FIG. 6 illustrates the vessel and the base of FIG. 5, following theconnection of a hydroelectric turbine to the supports; and

FIG. 7 illustrates the vessel positioned at a deployment site, loweringthe base and turbine towards the seabed.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to the accompanying drawings, there is described and showna system and method for the deployment of a hydroelectric turbine 10(only shown in FIGS. 6 and 7), which system comprises the use of a base12 for the turbine 10, and a vessel 14 to which the base 12 may becoupled, as will be described hereinafter in detail. The system andmethod of the invention, as will become apparent, substantially avoidsthe requirement for the use of heavy lifting equipment in the deploymentof the hydroelectric turbine 10, and thus significantly simplifies thedeployment process.

In the embodiment illustrated the base 12 comprises a triangular frame16 having three legs 18, although it will be understood from thefollowing description of the system and method of the invention that thebase 12 is an exemplary embodiment and could be of any other shapeand/or configuration. In order to begin deployment, the base 12 ispositioned on a quay Q beside a body of water W, for example the sea.The base 12 may be transported to the quay Q fully assembled, or morepreferably may be assembled on the quay Q from the component partsthereof

Referring then to FIG. 2, the base 12 is raised off the quay Q andlowered onto the seabed B adjacent to the quay Q. At this point theframe 12 is relatively lightweight and can be manoeuvred off the quay Qusing a relatively small crane (not shown) or the like. A lifting line20 and associated buoy 22 is connected to each corner of the base 12,preferably prior to lowering of the base 12 onto the seabed B. Thenumber of lifting lines 20 may be varied depending on the size and shapeof the base 12, or to meet any other operational requirements.

Referring now to FIG. 3, the vessel 14 is manoeuvred into positiondirectly above the base 12, beside the quay Q. The vessel 14 is providedwith load bearing means in the form of three winches 24, to each ofwhich winches 24 one of the lifting lines 20 can be secured. The winches24 can thus be used to raise the base 12 into a position beneath thevessel 14, as illustrated in FIG. 4. It will of course be appreciatedthat any other functional equivalent to the winches 24 could beemployed, and indeed the number of winches 24 and the positions thereofmay be varied as required. The vessel 14 and/or base 12 may be providedwith locking means (not shown) adapted to secure the base 12 to theunderside of the vessel 14 once winched into position. The load willtherefore be removed from the winches 24 once the base 12 is locked inposition. The winches 24 may however serve as this locking means.

It can be seen that the vessel 14, in the embodiment illustrated, iscomprised of a pair of hulls in the form of pontoons 26, which areconnected to one another by a pair of cross members 28. The spacebetween the cross members 28 is left empty such as to define a portal 30in the vessel 14. The base 12 can therefore be accessed through theportal 30 from above the vessel 14. Thus referring to FIG. 5 a pair ofsupports 32 are now connected to the base 12, which work can beundertaken from onboard the vessel 14. As used herein, the term“support” is intended to mean any system or mechanism which enables theturbine 10 to be connected to the base 12 in a suitable fashion, and maynot necessarily be of the upright nature depicted by the pair ofsupports 32 illustrated.

As the base 12 is now safely secured beneath the vessel 14, if requiredballast can be added to the base 12 in order to bring the weight of thebase 12 to a level which will allow the base 12 and turbine 10 to sitsecurely on the seabed under their own weight. As this ballast is onlyadded at this stage, the winches 24 do not need to bear this extra loadwhen raising the base 12 into position beneath the vessel 14. The addingof ballast at this stage also ensures that when the base 12 is firstlifted off the quay Q and lowered to the seabed B, the crane undertakingthe lift does not have to bear the weight of the ballast, and so arelatively small crane can be employed.

Turning then to FIG. 6, the turbine 10 is now lifted onto the base 12,and in particular the supports 32, again using a relatively small cranepositioned on the quay Q. The turbine 10 is then secured to the supports32 and is then ready to be transported to a deployment site out at sea.

It is envisaged that as this turbine based technology matures, theturbines will grow in size, and so therefore will the distance betweenthe hulls or pontoons 26. However, the winch 24 which is located on themiddle of the front cross member 28 will be carrying a significant load,and is not supported. It is thus envisaged that the design of the vessel14 for larger turbines (or indeed if two or more turbines 10 are to bemounted side by side on a single base 12) will take some form other thana catamaran design, for example a tri-maran. The modular nature of thevessel 14 would make such a modification possible and readilyachievable.

In addition, the modular nature of the vessel 14 enables the vessel 14to be easily dismantled and shipped around the world to the nextinstallation site in the hull of a large cargo ship. This approach maysave time as the larger cargo ships are able to travel in far worseconditions than the vessel 14. The modular approach also means that thevessel 14 could be reconfigured in the future for different shaped bases12, i.e. when deploying a larger turbine it may be desirable to widenthe distance between the hulls 26, which could be easily done bylengthening the cross members 28. This has obvious cost savings as it isnot necessary to build a completely new vessel.

Another advantage embodied by the shape of the vessel 14 is that it iseasy to tow as there is very little resistance, as the cross members 28are positioned to be out of the water and so only the pontoons 26 aresitting in the water. This design will align itself with the tidal flowcompared with an alternate design having the cross members submerged.The latter design will be less streamlined and less likely to be in linewith the flow. This is an important feature when deploying the turbine10 when there is some tide running as when the turbine 10 is lowered,the vessel 14 will be orientated correctly to the tide and so theturbine 10 will be automatically deployed in the correct orientation.

The modular approach to the design of the vessel 14 also allowsadditional equipment to be quickly and easily mounted to the vessel 14for use during the installation process. Platforms (not shown)supporting such equipment can be easily connected to the vessel 14 usingconventional modular connectors (not shown).

Referring to FIG. 7, once the vessel 14, base 12 and turbine 10 havebeen positioned above the deployment site the base 12 and turbine 10 canbe lowered into position. This is a simple process of unwinding thewinches 24 which will allow the base 12 to fall away from beneath thevessel 14. If any locking means (not shown) are provided on the base 12and/or vessel 14 they will need to be released before unwinding thewinches 24. The portal 30 in the vessel 14 is shaped and dimensioned toenable the turbine 10 to pass downwardly through the portal 30, and thusthe combined turbine 10 and base 12 can be lowered together from thevessel 14. No further work must then be done in securing the twotogether when the base 12 has been positioned on the seabed B, therebygreatly simplifying the deployment process. In addition, no liftingequipment such as cranes or the like are required to be operated fromonboard the vessel 14.

The connectivity between the base 12 and vessel 14 also allows the aboveprocess to be carried out in reverse, in order to allow the base 12 andturbine 10 to be retrieved from the seabed B. The vessel 14 ispositioned over and connected to the base 12, which can then be winchedinto position beneath the vessel 12, and securely connected therebeneathfor transport back to shore or any other desired location.

It is preferable, prior to transporting the turbine 10 to the deploymentsite, that various tests are undertaken on the turbine 10 and the base12 while positioned adjacent to the quay Q. Thus referring to FIG. 6,once the turbine 10 has been secured to the base 12, the base 12 andturbine 10 are lowered to the seabed B, while the vessel 14 remainsadjacent the quay Q. The lifting lines 20 are left secured between thebase 12 and vessel 14 while the base 12 is positioned on the seabed B,in order to allow the base 12 and turbine 10 to be quickly and easilyretracted into position beneath the vessel 14 for transport to thedeployment site illustrated in FIG. 7. When the base 12 is positioned onthe seabed B, various tests can be carried out, for exampletesting/calibration of telemetry sensors (not shown) or the likepositioned on the base 12 and/or turbine 10. Once said testing has beencompleted, the base 12 is winched back into position beneath the vessel14, and the turbine 10 is then again positioned above deck of the vessel14. The vessel 14 can then be transported to the deployment site asdescribed herein before with reference to FIG. 7. If this testingreveals any problems with any aspect of the turbine 10 or base 12, bothcan quickly be removed from the water W due to being still positionedadjacent the quay Q. Indeed if there is only a problem with some aspectof the turbine 10, then the turbine 10 could be released from the base12 and taken onto the quay for further testing and/or repair. The base12 could then be left secured beneath the vessel 14 to await the returnof the repaired turbine 10.

It is envisaged that the system of the invention may be used to deploythe base 12 onto the seabed B without the turbine 10 mounted thereto,which would then be subsequently connected to the base 12 by suitablemeans.

It will therefore be appreciated that the system and method of thepresent invention provide a simplified yet highly efficient means ofdeploying a hydroelectric turbine 10, and minimises the requirement forheavy lifting equipment, eliminating the need for the use of suchequipment on board the vessel 14, in particular at the deployment site.

1. A hydroelectric turbine deployment system comprising a base (12) anda hydroelectric turbine (10) supportable on the base (12); a marinevessel (14) adapted to releasably retain, when afloat, the base (12)therebeneath; wherein the vessel (14) is adapted to allow the base (12)to be released and lowered away from, and/or raised under and connectedto, the vessel (14); and in which the base (12) comprises a support (32)which projects, when the base (12) is connected beneath the vessel (14),upwardly through the vessel (14); characterised in that the vessel (14)comprises a portal (30) through which the support (32) projects when thebase (12) is mounted beneath the vessel (14) and through which thesupport mounted turbine (10) can pass.
 2. A hydroelectric turbinedeployment system according to claim 1 in which the vessel (14)comprises load bearing means (24) adapted to raise and/or lower the base(12) relative to the vessel (14).
 3. A hydroelectric turbine deploymentsystem according to claim 2 in which the load bearing means (24)comprises one or more winches (24).
 4. A hydroelectric turbinedeployment system according to claim 1 which the vessel (14) comprisesat least a pair of hulls (26) connected together.
 5. A hydroelectricturbine deployment system according to claim 1 in which the system isadapted to enable ballast to be secured to the base (12) when the base(12) is secured beneath the vessel (14).
 6. A hydroelectric turbinedeployment system according to claim 1 which the vessel (14) is modular.7. A method of deploying a hydroelectric turbine (10) comprising thesteps of; securing a base (12) for the turbine (10) beneath a vessel(14); securing the turbine (10) to a support (32) of the base (12) whichprojects upwardly through the vessel (14); transporting the vessel to adeployment site; releasing the base from beneath the vessel;characterised in that in the step of releasing the base from beneath thevessel, allowing the turbine to pass through the vessel.
 8. A methodaccording to claim 7 comprising, in the step of securing the base (12),locating the base (12) on the bottom of a body of water; positioning thevessel (14) above the base (12); and raising the base (12) into positionbeneath the vessel (14).
 9. A method according to claim 8 comprising thestep of securing one or more lifting lines (20) to the base (12) priorto locating the base (12) on the bottom of the body of water.
 10. Amethod according to claim 8 or 9 comprising, in the step of raising thebase (12) into position beneath the vessel (14), utilizing load bearingmeans (24) on the vessel (14).
 11. A method according to claim 7comprising the further step of adding ballast to the base (12)subsequent to securing the base (12) beneath the vessel (14).
 12. Amethod according to claim 7 comprising securing the support (32)to thebase (12) subsequent to securing the base (12) beneath the vessel (14).13. A method according to claim 7 comprising the further step of testingvarious operating parameters of the base (12) and/or turbine (10) at atest location prior to deploying the base (12) at the deployment site.